Continuous 80 Vdc
Transient (100ms) <100ms 100 Vdc
Operating Temperature Please refer to figure 27 for measuring point -40 114 °C
Storage Temperature -55 125 °C
Input/Output Isolation Voltage 1500 Vdc
INPUT CHARACTERISTICS
Operating Input Voltage 36 48 75 Vdc
Input Under-Voltage Lockout
Turn-On Voltage Threshold 33 34 35 Vdc
Turn-Off Voltage Threshold 31 32 33 Vdc
Lockout Hysteresis Voltage 1 2 3 Vdc
Maximum Input Current 100%load, 36Vin 2.9 A
No-Load Input Current 100 150 mA
Off Converter Input Current 5 10 mA
Inrush Current(I2t) 0.015 A2s
Input Reflected-Ripple Current P-P thru 12µH inductor, 5Hz to 20MHz 10 mA
Input Voltage Ripple Rejection 120Hz 50 dB
OUTPUT CHARACTERISTICS
Output Voltage Set Point
Output Voltage Regulation
Over Load
Over Line Vin=36V to 75V,Io1=Io2=full load
Cross Regulation Worse Case ±5 ±10 mV
Over Temperature
Total Output Voltage Range Over sample load, line and temperature
Output Voltage Ripple and Noise 5Hz to 20MHz bandwidth
Peak-to-Peak Io1, Io2 Full Load, 1µF ceramic, 10µF tantalum
RMS Io1, Io2 Full Load, 1µF ceramic, 10µF tantalum
Operating Output Current Range
Output DC Current-Limit Inception
DYNAMIC CHARACTERISTICS
Output Voltage Current Transient 48V, 10µF Tan & 1µF Ceramic load cap, 0.1A/µs
Positive Step Change in Output Current Iout1from 50% Io, max to 75% Io, max
Negative Step Change in Output Current Iout2 from 75% Io, max to 50% Io, max
Cross dynamic Each channel independence 20 mV
Settling Time (within 1% Vout nominal) 150 US
Turn-On Transient
Start-up Time, From On/Off Control 10 15 MS
Start-up Time, From Input 10 15 mS
Maximum Output Capacitance Full load; 5% overshoot of Vout at startup
EFFICIENCY
100% Load Iout1, Iout2 full load, 48vdc Vin 88 %
60% Load Iout1, Iout2 60% of full load, 48vdc Vin 88 %
Figure 1: Efficiency vs. load current Iout1 for minimum,
nominal, and maximum input voltage at 25
Figure 3: Efficiency vs. load current Iout1 and Iout2 for
minimum, nominal, and maximum input voltage at 25
Iout1=Iout2
°C, for Iout2=7.5A.
°C, for
Figure 2: Efficiency vs. load current Iout2 for minimum,
nominal, and maximum input voltage at 25
Figure 4: Power dissipation vs. load current for minimum,
nominal, and maximum input voltage at 25°C. for Iout1=Iout2
°C, for Iout1=7.5A
DS_Q48DR1R833_03162007
3
ELECTRICAL CHARACTERISTICS CURVES
Vout2
Vout1
Figure 5: Turn-on transient at zero load current(2ms/div).
Vin=48V. Negative logic turn on. Top Trace: Vout; 1V/div;
Bottom Trace: ON/OFF input: 5V/div
Vout2
Vout2
Vout1
Figure 6: Turn-on transient at full rated load current (resistive
load) (2 ms/div). Vin=48V. Negative logic turn on. Top Trace:
Vout; 1V/div; Bottom Trace: ON/OFF input: 5V/div
Vout2
Vout1
Figure 7: Turn-on transient at zero load current (2ms/div).
Vin=48V. Positive logic turns on. Top Trace: Vout; 1V/div;
Bottom Trace: ON/OFF input: 5V/div
Figure 8: Turn-on transient at full load current (2ms/div).
Vin=48V. Positive logic turns on. Top Trace: Vout; 1V/div;
Bottom Trace: ON/OFF input: 5V/div
Vout1
DS_Q48DR1R833_03162007
4
ELECTRICAL CHARACTERISTICS CURVES
)
ELECTRICAL CHARACTERISTICS CURVES
Ch1
Ch2
Ch3
Ch4
Figure 9: Output voltage response to step-change in load
Fteigure 9:Typical full load input characteristics at room
current Iout2 (75%-50%-75% of Io, max; di/dt = 2.5A/µs) at
mperature
Iout1=7.5A. Load cap: 470µF, 35m
Ω
ESR solid electrolytic
capacitor and 1µF ceramic capacitor. Ch1=Vout2
(100mV/div), Ch2=Iout2 (7.5A/div), Ch3=Vout1 (100mV/div) ,
Ch4=Iout1 (7.5A/div) Scope measurement should be made
using a BNC cable (length shorter than 20 inches). Position
the load between 51 mm to 76 mm (2 inches to 3 inches)
from the module.
Ch1
Ch1
Ch2
Ch3
Ch3
Ch4
Ch4
6
Figure 10: Output voltage response to step-change in load
F
igure 10:Output voltage response to step-change in load
current Iout1 (75%-50%-75% of Io, max; di/dt = 2.5A/µs) at
cu
rrentIout2(75%-50%-75% of Io, max; di/dt = 0.1A/µs) at
Iout2=7.5A. Load cap: 470µF, 35m
I
o
ut1=7.5A. Load cap: 10µF, tantalum capacitor and 1µF ceramic
capacitor and 1µF ceramic capacitor. Ch1=Vout2 (100mV/div),
(7.5A/div) Scope measurement should be made using a BNC
m
easurement should be made using a BNC cable (length shorter
cable (length shorter than 20 inches). Position the load between
thmm (2
an20 inches). Position the load between51 mm to 76
51 mm to 76 mm (2 inches to 3 inches) from the module.
inches to 3 inches) from the module.
Ω
ESR solid electrolytic
Ch1
Ch1
Ch2
Ch2
Ch3
Ch3
Ch4
Ch4
Figure 11: Output voltage response to step-change in load
current Iout2 and Iout1 (75%-50%-75% of Io, max; di/dt =
2.5A/µs). Load cap: 470µF, 35m
F
igure 11:Output voltage response to step-change in load
capacitor and 1µF ceramic capacitor. Ch1=Vout2
c
urrentIout1(75%-50%-75% of Io, max; di/dt = 0.1A/µs) at
(100mV/div), Ch2=Iout2 (7.5A/div), Ch3=Vout1 (100mV/div) ,
Io
ut2=7.5A. Load cap: 10µF,tantalum capacitor and 1µF
Ch4=Iout1 (7.5A/div) Scope measurement should be made
c
eramic capacitor. Ch1=Vout2 (100mV/div), Ch2=Iout2
using a BNC cable (length shorter than 20 inches). Position
(
7.5A/div),Ch3=Vout1 (100mV/div), Ch4=Iout1 (7.5A/div)
the load between 51 mm to 76 mm (2 inches to 3 inches)
S
copemeasurement should be made using a BNC cable
from the module.
(ln20inches). Position the load between
ength shortertha
51 mm to 76 mm (2 inches to3 inches) from the module.
Ω
ESR solid electrolytic
Ch1
Ch2
Ch3
Ch4
Figure 12: Test set-up diagram showing measurement points for
Input Terminal Ripple Current and Input Reflected Ripple
Current.
cF:Output voltage response to step-change in load
igure12
Note: Measured input reflected-ripple current with a simulated
u
rrentIout2and Iout1 (75%-50%-75% of Io, max; di/dt =
source Inductance (L
0.
1A/µs). Load cap: 10µF, tantalum capacitor and 1µF ceramic
battery impedance. Measure current as shown above
ca7.5A/div),
pacitor. Ch1=Vout2 (100mV/div), Ch2=Iout2(
of 12 µH. Capacitor Cs offset possible
TEST
Ch3=Vout1 (100mV/div), Ch4=Iout1 (7.5A/div) Scopemeasurement should be made using a BNC cable (length shorter than 20 inches). Position the load between51 mm to 76mm (2inches to 3 inches) from the module.
DS_Q48DR1R833_03162007
5
ELECTRICAL CHARACTERISTICS CURVES
V
)
Figure 13: Input Terminal Ripple Current-ic, at full rated
output current and nominal input voltage with 12µH source
impedance and 33µF electrolytic capacitor (500 mA/div,
2us/div).
StripCopper
Vo(+)
10u1u
SCOPERESISTI
LOAD
Vo(-)
Figure 14: Input reflected ripple current-i
source inductor at nominal input voltage and rated load c urrent
(20 mA/div, 2us/div).
, through a 12µH
s
Figure 15: Output voltage noise and ripple measurement
test setup
DS_Q48DR1R833_03162007
Figure 16: Output voltage ripple at nominal input voltage and
rated load current(Iout1=Iout2=15A)(20 mV/div, 1us/div
trace: Vout2(20mV/div), Bottom trace(20mV/div)
Load capacitance: 1µF ceramic capacitor and 10µF tantalum
capacitor. Bandwidth: 20 MHz. Scope measurements should be
made using a BNC cable (length shorter than 20 inches). Position
the load between 51 mm to 76 mm (2 inches to 3 inches) from
the module.
. Top
6
ELECTRICAL CHARACTERISTICS CURVES
Figure 17: Output voltage vs. load current Iout1 showing
typical current limit curves and converter shutdown points.
Figure 18: Output voltage vs. load current Iout2 showing typical
current limit curves and converter shutdown points.
DS_Q48DR1R833_03162007
7
DESIGN CONSIDERATIONS
Input Source Impedance
The impedance of the input source connecting to the
DC/DC power modules will interact with the modules
and affect the stability. A low ac-impedance input
source is recommended. If the source inductance is
more than a few µH, we advise adding a 10 to 100 µF
electrolytic capacitor (ESR < 0.7 Ω at 100 kHz)
mounted close to the input of the module to improve the
stability.
Layout and EMC Considerations
Delta’s DC/DC power modules are designed to operate
in a wide variety of systems and applications. For
design assistance with EMC compliance and related
PWB layout issues, please contact Delta’s technical
support team. An external input filter module is
available for easier EMC compliance design.
Application notes to assist designers in addressing
these issues are pending release.
Safety Considerations
The power module must be installed in compliance with
the spacing and separation requirements of the enduser’s safety agency standard, i.e., UL60950,
CAN/CSA-C22.2 No. 60950-00 and EN60950:2000 and
IEC60950-1999, if the system in which the power
module is to be used must meet safety agency
requirements.
When the input source is 60 Vdc or below, the power
module meets SELV (safety extra-low voltage)
requirements. If the input source is a hazardous voltage
which is greater than 60 Vdc and less than or equal to
75 Vdc, for the module’s output to meet SELV
requirements, all of the following must be met:
The input source must be insulated from any
hazardous voltages, including the ac mains, with
reinforced insulation.
One Vi pin and one Vo pin are grounded, or all the
input and output pins are kept floating.
The input terminals of the module are not operator
accessible.
If the metal baseplate is grounded the output must
be also grounded.
A SELV reliability test is conducted on the system
where the module is used to ensure that under a
single fault, hazardous voltage does not appear at
the module’s output.
Do not ground one of the input pins without grounding
one of the output pins. This connection may allow a
non-SELV voltage to appear between the output pin
and ground.
The power module has extra-low voltage (ELV) outputs
when all inputs are ELV.
This power module is not internally fused. To achieve
optimum safety and system protection, an input line
fuse is highly recommended. The safety agencies
require a normal-blow fuse with 7A maximum rating to
be installed in the ungrounded lead. A lower rated fuse
can be used based on the maximum inrush transient
energy and maximum input current.
Soldering and Cleaning Considerations
Post solder cleaning is usually the final board assembly
process before the board or system undergoes
electrical testing. Inadequate cleaning and/or drying
may lower the reliability of a power module and
severely affect the finished circuit board assembly test.
Adequate cleaning and/or drying is especially important
for un-encapsulated and/or open frame type power
modules. For assistance on appropriate soldering and
cleaning procedures, please contact Delta’s technical
support team.
DS_Q48DR1R833_03162007
8
FEATURES DESCRIPTIONS
Over-Current Protection
The modules include an internal output over-current
protection circuit, which will endure current limiting for
an unlimited duration during output overload. If the
output current exceeds the OCP set point, the modules
will automatically shut down (hiccup mode).
The modules will try to restart after shutdown. If the
overload condition still exists, the module will shut down
again. This restart trial will continue until the overload
condition is corrected.
Over-Voltage Protection
The modules include an internal output over-voltage
protection circuit, which monitors the voltage on the
output terminals. If this voltage exceeds the overvoltage set point, the module will shut down.
The module will try to restart after shutdown. If the overvoltage condition still exists during restart, the module
will shut down again. This restart trial will continue until
the output voltage is within specification.
Over-Temperature Protection
The over-temperature protection consists of circuitry
that provides protection from thermal damage. If the
temperature exceeds the over-temperature threshold
the module will shut down.
The module will try to restart after shutdown. If the overtemperature condition still exists during restart, the
module will shut down again. This restart trial will
continue until the temperature is within specification.
Remote On/Off
The remote on/off feature on the module can be either
negative or positive logic. Negative logic turns the
module on during a logic low and off during a logic high.
Positive logic turns the modules on during a logic high
and off during a logic low.
Remote on/off can be controlled by an external switch
between the on/off terminal and the Vi(-) terminal. The
switch can be an open collector or open drain.
For negative logic if the remote on/off feature is not
used, please short the on/off pin to Vi(-). For positive
logic if the remote on/off feature is not used, please
leave the on/off pin to floating.
Figure 19: Remote on/off implementation
Output Voltage Adjustment (TRIM)
To increase or decrease the output voltage set point,
the modules may be connected with an external
resistor between the TRIM pin and either Vout1(+) or
RTN. The TRIM pin should be left open if this feature
is not used.
Figure 20: Circuit configuration for trim-down (decrease
output voltage)
If the external resistor is connected between the TRIM
and Vout1(+) pin, the output voltage set point
decreases (Fig. 20). The external resistor value is
from the table below.
DS_Q48DR1R833_03162007
9
FEATURES DESCRIPTIONS (CON.)
Figure 21: Circuit configuration for trim-up (increase output
voltage)
If the external resistor is connected between the TRIM
and RTN, the output voltage set point increases (Fig.
21). The external resistor value is from table below.
The output voltage can be increased by the trim pin,
When using trim; the output voltage of the module is
usually increased, which increases the power output of
the module with the same output current. Care should
be taken to ensure that the maximum output power of
the module remains at or below the maximum rated
power.
Thermal management is an important part of the
system design. To ensure proper, reliable operation,
sufficient cooling of the power module is needed over
the entire temperature range of the module. Convection
cooling is usually the dominant mode of heat transfer.
Hence, the choice of equipment to characterize the
thermal performance of the power module is a wind
tunnel.
Thermal Testing Setup
Delta’s DC/DC power modules are characterized in
heated vertical wind tunnels that simulate the thermal
environments encountered in most electronics
equipment. This type of equipment commonly uses
vertically mounted circuit cards in cabinet racks in which
the power modules are mounted.
The following figure shows the wind tunnel
characterization setup. The power module is mounted
on a test PWB and is vertically positioned within the
wind tunnel. The space between the neighboring PWB
and the top of the power module is constantly kept at
6.35mm (0.25’’).
Thermal Derating
Heat can be removed by increasing airflow over the
module. The module’s hottest spot is less than +114°C.
To enhance system reliability, the power module should
always be operated below the maximum operating
temperature. If the temperature exceeds the maximum
module temperature, reliability of the unit may be
affected.
FACING PWB
PWB
THERMAL CURVES
Figure 23: Hot spot temperature measured point
*
The allowed maximum hot spot temperature is defin ed at
℃
114
110%
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
2025303540455055606570758085
Figure 24: Output load vs. ambient temperature and air velocity
@V
Q48DR1R833(Standard) Output Load vs. Ambient Temperature and Air Velocity
Output Load(%)
Natural
Convection
=48V(Transverse Orientation)
in
@ Vin = 48V (Transverse Orientation)
100LFM
200LFM
300LFM
600LFM
500LFM
400LFM
Ambient Temperature (℃)
AIR VELOCIT
AND AMBIENT
TEMPERATURE
MEASURED BELOW
THE MODULE
Note: Wind Tunnel Test Setup Figure Dim nsions are in millimeters and (Inche
Figure 22: Wind tunnel test setup
DS_Q48DR1R833_03162007
MODULE
50.8 (2.0”)
IR FLOW
12.7 (0.5”)
e
11
MECHANICAL DRAWING
Pin No. Name Function
1
2
3
4
5
6
7
8
-Vin
ON/OFF
+Vin
+Vout2
TRIM
Output RTN
+Vout1
Optional
Notes:
1
2
DS_Q48DR1R833_03162007
Pins 1-8 are 1.00mm (0.040”) diameter
All pins are copper with Tin plating.
Negative input voltage
Remote ON/OFF
Positive input voltage
Positive output voltage2
Output voltage trim
Telephone:
East Coast: (888) 335 8201
West Coast: (888) 335 8208
Fax: (978) 656 3964
DCDC@delta-corp.com
Email:
WARRANTY
Delta offers a two (2) year limited warranty. Complete warranty information is listed on our web site or is available
upon request from Delta.
Information furnished by Delta is believed to be accurate and reliable. However, no responsibility is assumed by Delta
for its use, nor for any infringements of patents or other rights of third parties, which may result from its use. No license
is granted by implication or otherwise under any patent or patent rights of Delta. Delta reserves the right to revise
these specifications at any time, without notice